U.S. patent number 7,262,374 [Application Number 11/455,638] was granted by the patent office on 2007-08-28 for pointing device and key sheet for pointing device.
This patent grant is currently assigned to Asahi Kasel EMD Corp., Polymatech Co. Ltd.. Invention is credited to Masami Arai, Yoshifumi Honmatsu, Toshinori Takatsuka.
United States Patent |
7,262,374 |
Takatsuka , et al. |
August 28, 2007 |
**Please see images for:
( Certificate of Correction ) ** |
Pointing device and key sheet for pointing device
Abstract
Provided are a pointing device allowing accurate depressing
operation on a key top and involving no erroneous input or
erroneous operation, and a key sheet for the pointing device. On
the back surface of a base sheet (14) of a key sheet (15) for a
pointing device, an accommodating portion (17) for a magnet (13),
for accommodating portion greatly protrudes toward a board (P)
beyond a pusher (14b) is provided. When the key top (12) is
depressed, the accommodating portion (17) and the magnet (13) come
into contact with the board (P), and causes the depressed key top
(12) to tilt using the point of contact as a fulcrum, thereby
pressing the pusher (14b) against a contact switch (Pi, Po). Thus,
it is possible to reduce the thickness and weight of the pointing
device (10) and the key sheet (15) for the pointing device.
Further, a reduction is achieved in terms of the possibility of
erroneous input and erroneous operation, making it possible to
reliably effect confirmation input.
Inventors: |
Takatsuka; Toshinori (Fuji,
JP), Honmatsu; Yoshifumi (Tokyo, JP), Arai;
Masami (Tokyo, JP) |
Assignee: |
Asahi Kasel EMD Corp. (Tokyo,
JP)
Polymatech Co. Ltd. (Tokyo, JP)
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Family
ID: |
36928387 |
Appl.
No.: |
11/455,638 |
Filed: |
June 20, 2006 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060284710 A1 |
Dec 21, 2006 |
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Foreign Application Priority Data
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Jun 21, 2005 [JP] |
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2005-180340 |
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Current U.S.
Class: |
200/5A; 335/205;
200/61.45M; 345/160; 200/512 |
Current CPC
Class: |
G06F
3/0202 (20130101); H01H 13/705 (20130101); H01H
2221/014 (20130101); H01H 2221/006 (20130101); H01H
2221/012 (20130101); H01H 2239/024 (20130101); H01H
2217/018 (20130101); H01H 2221/016 (20130101); H01H
2217/024 (20130101) |
Current International
Class: |
H01H
9/30 (20060101) |
Field of
Search: |
;200/5A,512-513,520,341,61.45M ;335/192,205-207 ;345/156-160 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2000-235822 |
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Aug 2000 |
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JP |
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2002-150904 |
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May 2002 |
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JP |
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2004-062447 |
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Feb 2004 |
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JP |
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Primary Examiner: Lee; K. Richard
Attorney, Agent or Firm: Rader, Fishman & Grauer
PLLC
Claims
What is claimed is:
1. A key sheet for a pointing device, comprising: a key top; a base
sheet formed of a rubber-like elastic material having, on a back
surface of the base sheet opposed to a board, a protrusion-like
pusher opposed to a contact switch provided on the board, and
having the key top on a front surface of the base sheet on the side
opposite to the back surface; and a magnet provided on the base
sheet, the pusher being displaced toward the board through a
depressing operation of the key top to depress the contact switch
provided on the board, the magnet being laterally moved through
elastic deformation of the base sheet as a result of a lateral
moving operation of the key top to cause a change in magnetic flux
density with respect to a magnetic sensor provided on the board,
wherein an accommodating portion for the magnet for accommodating
portion greatly protrudes toward the board beyond the pusher is
provided on the back surface of the base sheet, and wherein the
accommodating portion comes into contact with the board when the
key top is depressed and causes the key top depressed to tilt using
the point of contact as a fulcrum to thereby press the pusher
against the contact switch.
2. A key sheet for a pointing device according to claim 1, wherein
both the accommodating portion and the pusher are situated so that
the accommodating portion and the pusher at least partially overlap
the key top in the direction of the key top being depressed.
3. A key sheet for a pointing device according to claim 1, wherein
the accommodating portion and the pusher are arranged at positions
symmetrical with respect to the center of the key top.
4. A key sheet for a pointing device according to claim 1, wherein
a plurality of the pushers are provided, wherein the accommodating
portion is provided at the center of the key top, and wherein the
pushers are provided radially around the accommodating portion.
5. A key sheet for a pointing device, comprising: a key top; a base
sheet formed of a rubber-like elastic material having, on a back
surface of the base sheet opposed to a board, a protrusion-like
pusher opposed to a contact switch provided on the board, and
having the key top on a front surface of the base sheet on the side
opposite to the back surface; and a magnet provided on the base
sheet, the pusher being displaced toward the board through a
depressing operation of the key top to depress the contact switch
provided on the board, the magnet being laterally moved through
elastic deformation of the base sheet as a result of a lateral
moving operation of the key top to cause a change in magnetic flux
density with respect to a magnetic sensor provided on the board,
wherein an accommodating portion for the magnet for accommodating
portion retains the magnet while greatly protruding toward the
board beyond the pusher is provided on the back surface of the base
sheet, and wherein the magnet comes into contact with the board
when the key top is depressed and causes the key top depressed to
tilt using the point of contact as a fulcrum to thereby press the
pusher against the contact switch.
6. A key sheet for a pointing device according to claim 5, wherein
both the accommodating portion and the pusher are situated so that
the accommodating portion and the pusher at least partially overlap
the key top in the direction of the key top being depressed.
7. A key sheet for a pointing device according to claim 5, wherein
the accommodating portion and the pusher are arranged at positions
symmetrical with respect to the center of the key top.
8. A key sheet for a pointing device according to claim 5, wherein
a plurality of the pushers are provided, wherein the accommodating
portion is provided at the center of the key top, and wherein the
pushers are provided radially around the accommodating portion.
9. A pointing device equipped with a key sheet, and a board having
a contact switch and a magnetic sensor, the key sheet, comprising:
a key top; a base sheet formed of a rubber-like elastic material
having, on a back surface of the base sheet opposed to a board, a
protrusion-like pusher opposed to a contact switch provided on the
board, and having the key top on a front surface of the base sheet
on the side opposite to the back surface; and a magnet provided on
the base sheet, the pusher effecting depression input on the
contact switch upon a depressing operation of the key top, the
magnet being laterally moved through elastic deformation of the
base sheet as a result of a lateral moving operation of the key
top, at least one of the magnetic sensor detecting a change in
magnetic flux density as a result of the lateral movement, wherein
an accommodating portion for the magnet for accommodating portion
greatly protrudes toward the board beyond the pusher is provided on
the back surface of the base sheet, and wherein the accommodating
portion comes into contact with the board when the key top is
depressed and causes the key top depressed to tilt using the point
of contact as a fulcrum to thereby press the pusher against the
contact switch.
10. A pointing device according to claim 9, wherein both the
accommodating portion and the pusher are situated so that the
accommodating portion and the pusher at least partially overlap the
key top in the direction of the key top being depressed.
11. A pointing device according to claim 9, wherein the
accommodating portion and the pusher are arranged at positions
symmetrical with respect to the center of the key top.
12. A pointing device according to claim 9, wherein a plurality of
the pushers are provided, wherein the accommodating portion is
provided at the center of the key top, and wherein the pushers are
provided radially around the accommodating portion.
13. A pointing device according to claim 9, wherein the magnetic
sensor is provided on the back surface of the board not opposed to
the key sheet.
14. A pointing device equipped with a key sheet, and a board having
a contact switch and a magnetic sensor, the key sheet comprising: a
key top; a base sheet formed of a rubber-like elastic material
having, on a back surface of the base sheet opposed to a board, a
protrusion-like pusher opposed to a contact switch provided on the
board, and having the key top on a front surface of the base sheet
on the side opposite to the back surface; and a magnet provided on
the base sheet, the pusher effecting depression input on the
contact switch upon a depressing operation of the key top, the
magnet being laterally moved through elastic deformation of the
base sheet as a result of a lateral moving operation of the key
top, at least one of the magnetic sensor detecting a change in
magnetic flux density as a result of the lateral movement, wherein
an accommodating portion for the magnet for accommodating portion
retains the magnet while protruding greatly toward the board beyond
the pusher is provided on the back surface of the base sheet, and
wherein the magnet comes into contact with the board when the key
top is depressed and causes the key top depressed to tilt using the
point of contact as a fulcrum to thereby press the pusher against
the contact switch.
15. A pointing device according to claim 14, wherein both the
accommodating portion and the pusher are situated so that the
accommodating portion and the pusher at least partially overlap the
key top in the direction of the key top being depressed.
16. A pointing device according to claim 14, wherein the
accommodating portion and the pusher are arranged at positions
symmetrical with respect to the center of the key top.
17. A pointing device according to claim 14, wherein a plurality of
the pushers are provided, wherein the accommodating portion is
provided at the center of the key top, and wherein the pushers are
provided radially around the accommodating portion.
18. A pointing device according to claim 14, wherein the magnetic
sensor is provided on the back surface of the board not opposed to
the key sheet.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a pointing device to be used as an
operating device of an electronic apparatus, such as a mobile
phone, a PDA, or a game controller, and to a key sheet to be used
in the pointing device, in particular, a magnetism detection type
pointing device which detects a change in magnetic flux density
through lateral movement operation of a key top to determine a
lateral position of the key top and which also functions as a key
capable of performing confirmation input through key top depressing
operation, and to a key sheet for the pointing device.
2. Description of the Related Art
Operating devices for electronic apparatuses and the input systems
for them are being diversified. In this context, there is known a
magnetism detection type pointing device which detects with a
magnetic sensor a change in magnetic flux density due to "lateral
movement" of a magnet through, for example, tilting of a key top,
and which utilizes this change as a lateral position input signal.
Above all, a pointing device which also functions as a key capable
of confirmation input through key top depressing operation is used
as an input key of a mobile phone, etc., and is disclosed, for
example, in JP 2004-62447 A. As shown in FIG. 10, in such a
pointing device, a magnet is embedded and retained in a key top to
be operated.
In a magnetism detection type pointing device (1) as shown in FIG.
10, a magnet (2) is inside a key top (3), so the distance between
the magnet (2) and magnetic sensors (4) is rather large. Thus, to
attain a sufficient sensitivity property, it is necessary for the
magnet (2) to be large or for the magnetic force to be strong. An
attempt to meet this demand results in an increase in the thickness
of the key top (3), an increase in the weight of the pointing
device (1), etc. Further, when a magnet with strong magnetic force
is used, there is a fear of the magnetic force being leaked to the
exterior to adversely affect peripheral devices, a magnetic card,
etc.
Further, the key top (3) is used to effect directional input
(lateral position input) through lateral movement operation and
confirmation input through depression of a contact belleville
spring (Po) on a board (P) by depressing the key top in a direction
substantially perpendicular to the lateral movement direction to
thereby bring a board contact (Pi) into conduction, so that it is
necessary for the key top (3) to be capable of moving vertically
and horizontally. However, a large movable range for the key top
(3) and a high degree of freedom in movement thereof can lead to an
increase in the looseness of the key top (3) at the time of
operation, making it rather difficult to effect accurate depressing
operation. When the depressing operation is not properly effected
on the key top (3), erroneous input or erroneous operation
results.
SUMMARY OF THE INVENTION
The present invention may provide a pointing device of the type
which is capable of effecting directional input and confirmation
input, wherein it is possible to attain a reduction in thickness
and weight. The present invention may also provide a pointing
device, which does not easily involve erroneous input and erroneous
operation at the time of confirmation input.
Described herein is a key sheet for a pointing device, including: a
key top; a base sheet formed of a rubber-like elastic material,
having, on a back surface of the base sheet opposed to a board, a
protrusion-like pusher opposed to a contact switch provided on the
board, and having the key top on a front surface of the base sheet
on the side opposite to the back surface; and a magnet provided on
the base sheet, the pusher being displaced toward the board through
a depressing operation of the key top to depress the contact switch
provided on the board, the magnet being laterally moved through
elastic deformation of the base sheet as a result of a lateral
moving operation of the key top to cause a change in magnetic flux
density with respect to a magnetic sensor provided on the board, in
which an accommodating portion for the magnet for accommodating
portion greatly protrudes toward the board beyond the pusher is
provided on the back surface of the base sheet, and characterized
in that the accommodating portion comes into contact with the board
when the key top is depressed and causes the key top depressed to
tilt using the point of contact as a fulcrum to thereby press the
pusher against the contact switch.
In accordance with the present invention, there is further provided
a pointing device equipped with a key sheet and a board having a
contact switch and a magnetic sensor; the key sheet has a key top,
a protrusion-like pusher opposed to the contact switch and provided
on a back surface opposed to a board, a base sheet having the key
top on a front surface thereof on the side opposite to the back
surface and composed of a rubber-like elastic member, and a magnet
provided on the base sheet; when the key top is depressed, the
pusher effects depression input through the contact switch, and
when the key top is laterally moved, the magnet moves laterally
while causing elastic deformation of the base sheet, with the
magnetic sensor detecting a change in magnetic flux density due to
the lateral movement; there is provided on the back surface of the
base sheet a magnet accommodating portion greatly protruding toward
the board beyond the pusher; and the accommodating portion comes
into contact with the board when the key top is depressed, tilting
the depressed key top using the point of contact as a fulcrum to
press the pusher against the contact switch.
The key top may be provided on the front surface of the base sheet,
and the magnet accommodating portion greatly protruding toward the
board beyond the pusher is provided on the back surface of the base
sheet opposed to the board, with the magnet being provided in the
accommodating portion, so it is possible to place the magnet near
the board, making it possible to use a magnet of a weaker magnetic
force and smaller size than in the prior art. It is thus possible
to provide a key sheet for a pointing device and a pointing device
in which it is possible to achieve a reduction in magnetic flux
leakage, and a reduction in thickness and weight.
Further, at the time of depression of the key top, the magnet
accommodating portion may come into contact with the board, and the
depressed key top is tilted using the point of contact as the
fulcrum, so it is possible to reliably effect confirmation input
through the depression of the key top, and to reduce the risk of
erroneous input and erroneous operation.
The accommodating portion may come into contact with the board when
the key top is depressed. When the depressing operation is not
performed, the accommodating portion may be in or out of contact
with the board. In the case in which the accommodating portion is
in contact with the board, the key top can be tilted using the
point of contact as the fulcrum every time the key top is
depressed, so it is possible for the pusher to be reliably pressed
against the contact switch. When the key top is laterally moved,
the point of contact may slide on the board. Further, the pusher
may prevent excessive depression at the time of lateral movement of
the key top, so a stable operation is possible. In contrast, in the
case in which the accommodating portion is out of contact with the
board, the accommodating portion is not brought into contact with
the board at the time of lateral movement, so a smooth lateral
movement operation is possible.
Further, the present invention provides a key sheet for a pointing
device, including: a key top; a base sheet formed of a rubber-like
elastic material having, on a back surface of the base sheet
opposed to a board, a protrusion-like pusher opposed to a contact
switch provided on the board, and having the key top on a front
surface of the base sheet on the side opposite to the back surface;
and a magnet provided on the base sheet, the pusher being displaced
toward the board through a depressing operation of the key top to
depress the contact switch provided on the board, the magnet being
laterally moved through elastic deformation of the base sheet as a
result of a lateral moving operation of the key top to cause a
change in magnetic flux density with respect to a magnetic sensor
provided on the board, in which an accommodating portion for the
magnet for accommodating portion retains the magnet while greatly
protruding toward the board beyond the pusher is provided on the
back surface of the base sheet, and characterized in that the
magnet comes into contact with the board when the key top is
depressed and causes the key top depressed to tilt using the point
of contact as a fulcrum to thereby press the pusher against the
contact switch.
Still further, the present invention provides a pointing device
equipped with a key sheet, and a board having a contact switch and
a magnetic sensor, the key sheet, including: a key top; a base
sheet formed of a rubber-like elastic material having, on a back
surface of the base sheet opposed to a board, a protrusion-like
pusher opposed to a contact switch provided on the board, and
having the key top on a front surface of the base sheet on the side
opposite to the back surface; and a magnet provided on the base
sheet, the pusher effecting depression input on the contact switch
upon a depressing operation of the key top, the magnet being
laterally moved through elastic deformation of the base sheet as a
result of a lateral moving operation of the key top, a magnetic
sensor detecting a change in magnetic flux density as a result of
the lateral movement, in which an accommodating portion for the
magnet for accommodating portion retains the magnet while
protruding greatly toward the board beyond the pusher is provided
on the back surface of the base sheet, and characterized in that
the magnet comes into contact with the board when the key top is
depressed and causes the key top depressed to tilt using the point
of contact as a fulcrum to thereby press the pusher against the
contact switch.
Also in these aspects of the present invention, the key top is
provided on the front surface of the base sheet, and the magnet
accommodating portion is provided on the back surface of the base
sheet opposed to the board, with the accommodating portion
retaining the magnet so as to protrude greatly toward the board
beyond the pusher, so it is possible to place the magnet near the
board, making it possible to use a magnet of a weaker magnetic
force and smaller size than in the prior art. It is thus possible
to provide a key sheet for a pointing device and a pointing device
in which it is possible to achieve a reduction in magnetic flux
leakage, thickness, and weight.
Further, when the key top is depressed, the magnet may come into
contact with the board, and tilt the depressed key top using the
point of contact as the fulcrum to press the pusher against the
contact switch, so it is possible to reliably perform confirmation
input through the depression of the key top and to reduce the risk
of erroneous input and erroneous operation.
The magnet may come into contact with the board when the key top is
depressed. As with the accommodating portion, when the depressing
operation is not performed, the magnet may be in or out of contact
with the board. Assuming that the magnet is in contact with the
board, the key top can be tilted using the point of contact on the
board as the fulcrum every time the key top is depressed, so it is
possible to reliably press the pusher against the contact switch.
When the key top is laterally moved, the point of contact can slide
on the board. Further, the pusher may prevent excessive depression
at the time of lateral movement of the key top, so a stable
operation is possible. In contrast, assuming that the magnet is out
of contact with the board, the magnet does not come into contact
with the board at the time of lateral movement, so smooth lateral
movement is possible.
Regarding the arrangement of the accommodating portion and the
pusher, the accommodating portion and the pusher are provided such
that both of them at least partially overlap the key top in the
depressing direction of the key top. Since both the accommodating
portion and the pusher are provided such that both of them at least
partially overlap the key top in the direction in which the key top
is depressed, at least a part of each of the accommodating portion
and the pusher exists in the direction in which the key top is
depressed. Thus, the depressing force applied to the key top can be
transmitted to both the accommodating portion and the pusher. The
forward end of the accommodating portion protrudes beyond the
forward end of the pusher, so, when depressing operation is
performed on the key top, the accommodating portion or the magnet
in contact with the board serves as the fulcrum, and the key top
can be tilted in the normal tilting direction, making it possible
to accurately bring the contact switch into conduction by means of
the pusher.
In the present invention, the accommodating portion and the pusher
may be provided symmetrically with respect to the center of the key
top. Since the accommodating portion and the pusher are situated
symmetrically with respect to the center of the key top, the
accommodating portion and the magnet greatly protruding toward the
board beyond the pusher are brought into contact with the board
through the depression of the key top, and it is possible for the
pusher to reliably effect input on the contact switch, with the
accommodating portion or the magnet serving as the tilting fulcrum
for the key top.
Further, in these aspects of the present invention, it is also
possible to provide a plurality of the pushers, and to provide the
accommodating portion at the center of the key top, with the
pushers being provided radially around the accommodating portion.
Since the accommodating portion is provided at the center of the
key top, and a plurality of pushers are provided radially around
the accommodating portion, it is possible for the key top to be
tilted in a number directions using the accommodating portion at
the center of the key top as the tilting fulcrum, with the
plurality of pushers being pressed against a plurality of contact
switches provided on the board, so it is possible to effect
multi-directional input.
In the pointing device of the present invention, it is possible to
provide the magnetic sensor on the back surface of the board not
opposed to the key sheet. When the magnetic sensor is provided on
the back surface of the board not opposed to the key sheet, there
is no fear of the magnetic sensor coming into contact with the
magnet or the pusher as in the case in which the magnetic sensor is
provided on the front surface of the board, so it is possible to
achieve an increase in the degree of freedom in designing the size
and position of the magnet.
In the key sheet for a pointing device and the pointing device of
the present invention, it is possible to effect both lateral
position determination and confirmation input, and to achieve a
reduction in thickness and weight, with erroneous operation or
erroneous input not being easily involved at the time of
confirmation input. Thus, the present invention is particularly
applicable to a portable apparatus of which a compact design is
required and in which no upside or downside is fixed.
The contents of the present invention are not restricted to the
above-described constructions. The advantages, features, and uses
of this invention will become more apparent from the following
description given with reference to the accompanying drawings.
Further, it should be understood that all appropriate modifications
not departing from the gist of this invention are covered by the
scope of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a sectional view, taken along the line I-I of FIG. 2, of
a pointing device according to a first embodiment of the present
invention;
FIG. 2 is a plan view of the pointing device of the first
embodiment as mounted on an electronic apparatus;
FIG. 3 is an enlarged bottom view of a pusher and an accommodating
portion in a base sheet of the pointing device of the first
embodiment;
FIG. 4 is a sectional view of the pointing device of FIG. 1 as
depressed;
FIG. 5 is a sectional view, corresponding to FIG. 1, of a pointing
device according to a second embodiment;
FIG. 6 is a sectional view, taken along the line VI-VI of FIG. 7,
of a pointing device according to a third embodiment;
FIG. 7 is a plan view of the pointing device of the third
embodiment as mounted on an electronic apparatus;
FIG. 8 is an enlarged bottom view of a pusher and an accommodating
portion in a base sheet of the pointing device of the third
embodiment;
FIG. 9 is a sectional view, corresponding to FIG. 1, of a pointing
device according to a modification of the third embodiment; and
FIG. 10 is a sectional view of a conventional pointing device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, embodiments of the present invention will be
described with reference to the drawings. In the drawings, the
reference numerals indicate portions and components. In the
description of the embodiments, an abundant description of the
materials and structures common to those of the previously
described embodiment will be omitted.
First Embodiment {FIGS. 1 through 4}: as shown in FIGS. 1 and 2, in
a pointing device (10) according to this embodiment, opposed to a
board (P) provided with magnetic sensors (16) is a key sheet (15)
having a key top (12) exposed through the surface of a casing (11)
of an electronic apparatus. The electronic apparatus can be a
mobile phone, a personal digital assistant (PDA), a game
controller, a car navigation apparatus, or a car audio apparatus.
Moreover, the electronic apparatus can be operated with a finger.
Also shown is a base sheet (14) to which the key top (12) is firmly
attached and which retains a magnet (13) so as to allow it to make
lateral movement. At the ends (not shown) of the key sheet (15),
the key sheet (15) is held between the casing (11) and the board
(P). Thus, the interior of the electronic apparatus is isolated
from the exterior by the base sheet (14). By isolating the interior
of the electronic apparatus from the exterior, the intrusion of
foreign matter, such as dust or water, into the electronic
apparatus can be prevented.
The key top (12) may be configured from a hard resin. This hard
resin may include an elastomer resin, a polycarbonate resin, or an
ABS resin. Likewise, the key top (12) may be configured from metal
or the like. The configuration of the key top (12) may be in
conformity with various designs, such as a substantially
cylindrical configuration or a substantially parallelepiped-like
configuration. In addition, the configuration of the key top (12)
can include indicia such as characters, or various decorations
provided on the front surface or the back surface of the key top
(12). In the example shown, a mark (M1) is provided on the front
surface of the key top (12), indicating a depressing position for
effecting confirmation input. Further, in the lower portion of the
side surface of the key top (12), there is formed, as a portion of
the key top (12), a flange (12a) extending along the back surface
of the casing (11), serving as a mask for the base sheet (14) and
as a structure contributing to detachment prevention of the key top
(12). The key top (12) and the base sheet (14) can be firmly
attached to each other chemically by means of an adhesive, fusion
bonding, etc. or mechanically by means of clips, screws, etc.
The key top (12) can be firmly attached to the front surface of the
base sheet (14). The base sheet (14) may be formed of a rubber-like
elastic material. This rubber-like elastic material may be silicone
rubber or styrene-type thermoplastic elastomer. An accommodating
portion (17) and a pusher (14b) are formed on the back surface of
the base sheet (14), which is opposed to the board (P). Further,
the base sheet (14) may have, in the outer periphery of a key top
placing portion (14c) firmly attached to the key top (12), bellows
portions (14d). The bellows portions (14d) are adapted to expand
and contract as the key top (12) is laterally moved. The
accommodating portion (17), in which the magnet (13) is retained by
a rubber-like elastic material, greatly protrudes from the back
surface of the base sheet (14) toward the board (P) beyond the
pusher (14b). The accommodating portion (17) and the pusher (14b)
are situated off the center of the key top (12) and symmetrically
with respect to the center of the key top (12). Further, both the
accommodating portion (17) and the pusher (14b) are provided so as
to overlap the key top (12) at least partially in the direction in
which the key top (12) is depressed.
The portions constituting the base sheet (14) will be described.
First, the pusher (14b) is a portion to be pressed against a
contact belleville spring (Po) provided on the board (P) to bring a
board contact (Pi) into conduction. In other words, the pusher
(14b) is a portion of the base sheet (14) that is adapted to
depress a contact switch. This contact switch may consist of the
contact belleville spring (Po) and the board contact (Pi). As shown
in FIG. 4, the pusher (14b) may cause a part of the base sheet (14)
to protrude. It is also possible for the pusher (14b) to be formed
as a separate member. This separate member may be composed of a
hard resin. Moreover, the forward end of a convex portion of pusher
(14b) being covered with a film of small coefficient of friction is
also within the scope of the invention. In particular, the forward
end portion of the pusher (14b), which is held in contact with the
contact belleville spring (Po), may be formed in a configuration
and of a material of small coefficient of friction so as not to
interfere with the sliding operation.
The accommodating portion (17) is a portion for retaining the
magnet (13) on the key sheet (15), and is provided on the back
surface of the base sheet (14). To reliably obtain a tactile feel
at the time of depression, the accommodating portion (17) may be
arranged on the inner side of the key top (12) as a whole including
the flange (12a). In this embodiment, the accommodating portion
(17) is arranged at a position off the center of the key top (12).
By depressing the key top (12), it is possible to accurately
depress the single board contact (Pi). While no particular
limitations regarding the mode in which the magnet of the
accommodating portion (17) is retained, as shown in FIG. 1, by
injecting the base sheet material two times to surround the entire
surface of the magnet (13), it is advantageously hard for the
magnet (13) to be detached from the key sheet (15). In order that
the sliding operation of the key top (12) may not be impaired by
friction, a layer of a configuration and a material of small
coefficient of friction may be provided on the portion of the
accommodating portion (17) which is to be brought in contact with
the board (P).
The accommodating portion (17) may be in or out of contact with the
board (P). Even in the case in which accommodating portion (17) is
out of contact with the board (P), it may be necessary for the
bottom surface of the accommodating portion (17) to be brought into
contact with the board (P) before the board contact (Pi) is brought
into conduction at the time of depression of the key top (12), so
the forward end of the accommodating portion (17) protrudes beyond
the forward end of the pusher (14b). Further, there are no
particular limitations either regarding the configuration of the
bottom surface of the accommodating portion (17); the bottom
surface may be of a configuration not easily generating friction
with the board (P). Further, as shown, for example, in FIG. 3, in
order to reliably effect confirmation input, the bottom surface of
the accommodating portion (17) may be configured so as to have an
end portion (14e) crossing, substantially in a perpendicular manner
a phantom line projected onto the board (P) and connecting the
center (CA1) of the accommodating portion (17) and the center (CP1)
of the pusher (14b).
The bellows portion (14d) may be a portion adapted to expand and
contract at the time of lateral movement and depression of the key
top (12) to allow lateral movement and depressing movement of the
key top (12). For this purpose, the bellows portion (14d) can be
configured so to as to have a pleated fold. Likewise, the bellows
portion (14d) can be configured as a combination of thick-walled
and thin-walled portions. These configurations may effect the
expansion and contraction of the base sheet (14). The expansion and
contraction of the base sheet (14) may allow for the lateral
movement and depressing movement of the key top (12).
The magnet (13) retained by the accommodating portion (17) may be
selected from various types of magnet. These types of magnet may
include, but is not limited to, an Alnico magnet, a ferrite magnet,
a Sm--Co magnet, a neodymium magnet, or a plastic magnet formed by
filling powder of these magnets with resin, or the like.
To be utilized for the magnetic sensors (16) provided on the board
(P) are Hall elements, Hall ICs, magnetoresistive effect elements,
magnetoresistive effect ICs, etc. To attain the requisite magnetic
flux density, the magnet (13) and the magnetic sensors (16) are
appropriately selected and combined for use.
Next, the operation and effects of the pointing device (10) will be
described.
The key top (12) may be capable of moving to the right and left
directions of the plane as seen in FIG. 2 within the range of the
diameter of a penetration hole (11a) formed in the casing (11). The
key top (12) may allow depressing operation through the plane of
FIG. 2 toward the board (P).
That is, the bellows portions (14d) provided in the base sheet (14)
can expand and contract with the lateral movement of the key top
(12), so that when the key top (12) is moved, for example,
laterally to the right, the portion of the bellows portion (14d)
which is approached by the key top (12) is deformed so as to be
bent, and the portion of the bellows portion (14d) from which the
key top (12) departs is deformed so as to expand, whereby the key
top (12) supported by the key top placing portion (14c) is allowed
to move laterally. The force with which the laterally moved key top
(12) is restored to the initial position is mainly provided by the
bellows portions (14d).
On the other hand, as shown in FIG. 4, when depressing operation is
performed on the key top (12) in the direction perpendicular to the
lateral direction, the accommodating portion (17) may be held in
contact with the board (P) to constitute a fulcrum, and the pusher
(14b) may cause the contact belleville spring (Po) to buckle,
whereby a tactile feel can be generated, and the board contact (Pi)
brought into conduction. In this process, even if a position off
the mark (M1) indicating the depressing operation position for the
key top (12) is depressed, the key top (12) is tilted, with the
accommodating portion (17) being held in contact with the board (P)
to serve as a fulcrum, so that confirmation input is effected
accurately. In particular, in this embodiment, the bottom surface
of the accommodating portion (17) has the end portion (14e), so
that if, for example, a longitudinal side surface of the key top
(12) in FIG. 2 is depressed, i.e., off the center of the key top,
the depression is effected so as to cause the key top (12) to be
tilted in the correct tilting direction due to the end portion
(14e).
In this way, the key top (12) can be tilted through lateral
movement and depression. When the key top (12) is moved laterally,
the magnet (13) is moved laterally together with the key top (12),
whereby the distance between the magnet (13) and the magnetic
sensors (16) is changed. The magnetic sensors (16) read a change in
magnetic flux density due to this change in distance, so it is
possible to sense the position in the horizontal direction.
Further, through depression of the key top (12), the contact
belleville spring (Po) and the board contact (Pi) are brought into
conduction, making it possible to effect switch input, such as
confirmation input.
In the pointing device (10), the magnet (13) is not accommodated in
the key top (12) but is accommodated in the accommodating portion
(17) provided on the other side surface of the base sheet (14), so
that it is possible to reduce the distance between the magnet (13)
and the magnetic sensors (16), and to reduce the thickness of the
key top (12). Further, it is possible to perform depressing
operation on the key top (12) in which the key top (12) is tilted
using the accommodating portion (17) as the fulcrum. In particular,
the accommodating portion (17) may be at a position off the center
of the key top (12), and the pusher (14b) and the accommodating
portion (17) may be on the opposite sides with respect to the key
top center, so that it is possible to effect confirmation input
accurately no matter which portion of the key top (12) may be
depressed.
Second Embodiment {FIG. 5}: FIG. 5 shows a pointing device (20)
according to the second embodiment of the present invention. In
contrast to the pointing device (10) of the first embodiment, in
the pointing device (20), the configuration of an accommodating
portion (27) provided on a base sheet (24) is changed. That is, a
part of a magnet (23) is exposed, and the magnet (23) protrudes
from the forward end of the accommodating portion (27). Since a
part of the magnet (23) is exposed, the mounting of the magnet (23)
can be easy to perform. Further, the coefficient of friction of the
magnet (23) is smaller than that of the rubber-like elastic
material, so that the frictional resistance offered by the board
(P) is advantageously less. Further, it is possible to make the
distance between the magnet (23) and the magnetic sensors (16)
smaller. The retention of the magnet (23) may be effected by
bonding the magnet (23) to the interior of the accommodating
portion (27).
In the pointing device (20) also, it is possible to perform
depressing operation on the key top (12) using the accommodating
portion (27) as the fulcrum, and it is possible to effect accurate
confirmation input no matter what portion of the key top (12) may
be depressed.
The base sheet (24), the pusher (24b), the key top placing portion
(24c), the bellows portions (24d), and the key sheet (25) of the
second embodiment respectively correspond to the base sheet (14),
the pusher (14b), the key top placing portion (14c), the bellows
portions (14d), and the key sheet (15) of the first embodiment.
Third Embodiment {FIGS. 6 through 8}: FIGS. 6 through 8 show the
third embodiment of the present invention. In a pointing device
(30) according to this embodiment, an accommodating portion (37)
may be provided such that the projected position of the
accommodating portion (37) on a depressing operation surface (32b)
of a key top (32) can be at the center of the depressing operation
surface (32b). And, four pushers (34b) may be provided at equal
intervals in the circumference of the same circle whose center is
the accommodating portion (37). In other words, the accommodating
portion (37) can be provided at the center of the key top (32), and
four pushers (34b) may be arranged radially around the
accommodating portion (37). And, the key top (32) can be moved
laterally by 360 degrees from the center toward the outer
periphery, allowing lateral position input by 360 degrees. Further,
four marks (M2) indicating the depressing positions for the key top
(30) are provided in the depressing operation surface (32b). By
performing depressing operation at the four marks (M2), four
independent confirmation inputs are possible.
FIG. 8 shows a vertical phantom line (L1) connecting the center
(CA2) of the accommodating portion (37) and the centers of (CP2) of
the vertically arranged pushers (34b) as projected on the board (P)
and a horizontal phantom line (L2) connecting the center (CA2) of
the accommodating portion (37) and the centers of (CP2) of the
horizontally arranged pushers (34b) as projected on the board (P).
As shown in the drawing, the accommodating portion (37) has, at its
bottom, end portions (34f, 34h) extending so as to cross the
phantom line (L1) substantially in a perpendicular manner and end
portions (34e, 34g) extending so as to cross the phantom line (L2)
substantially in a perpendicular manner. Thus, no matter what
portion of the key top (32) may be depressed, the board contact
(Pi) closest to the depressing position is accurately brought into
conduction. In the case in which the accommodating portion (37) is
in contact with the board (P), it slides on the board (P) when the
key top (32) is moved laterally, and involves no excessive
depression of the key top (32), thus securing stable lateral
movement.
The base sheet (34), the key top placing portion (34c), the bellows
portions (34d), and the key sheet (35) of the third embodiment
respectively correspond to the base sheet (14), the key top placing
portion (14c), the bellows portions (14d), and the key sheet (15)
of the first embodiment.
Modification of the Third Embodiment {FIG. 9}: FIG. 9 shows a
modification of the third embodiment. In contrast to the pointing
device (30) of the third embodiment, in a pointing device (30')
according to this modification, the configuration of the
accommodating portion (37') provided on the base sheet (34') is
changed. That is, a part of the magnet (33') is exposed and
protrudes from the forward end of the accommodating portion (37').
As in the second embodiment, a part of the magnet (33') is exposed,
so that, the mounting of the magnet (33') is facilitated, the
frictional resistance respect to the board (P) can be reduced, and
the distance between the magnet (33') and the magnetic sensors (16)
can be further diminished. The retention of the magnet (33') may be
effected by bonding the magnet (33') to the interior of the
accommodating portion (37').
The base sheet (34') the pusher (34'b), the key top placing portion
(34'c), the bellows portions (34'd), and the key sheet (35') of the
modification of the third embodiment respectively correspond to the
base sheet (34), the pusher (34b), the key top placing portion
(34c), the bellows portions (34d), and the key sheet (35) of the
third embodiment.
Modifications of the Embodiments: the first through third
embodiments described above further allow the following
modifications.
While in the above embodiments the key top (12, 32) and the base
sheet (14, 24, 34) are formed as separate components, it is also
possible for the key top (12, 32) to be formed of a protrusion
provided through modification of the configuration of the base
sheet (14, 24, 34). That is, the key top (12, 32) may constitute a
part of the base sheet (14, 24, 34).
It is also possible to provide an internal light source, such as a
light-emitting diode (LED), on the board (P) to form the key top
(12, 32) as a so-called illumination type key top, in which
illumination can be effected through the key top (12, 32).
While the magnetic sensors (16) can be provided on the back surface
of the board (P), it is also possible for the magnetic sensors (16)
to be provided on the front surface of the board (P) insofar as the
magnetic sensors (16) do not interfere with the lateral movement
and depression movement of the key top (12, 32).
While confirmation input is possible at one position in the first
embodiment and at four positions in the third embodiment, it is
also possible to provide a pointing device in which confirmation
input is possible at two positions symmetrical with respect to the
accommodating portion.
The description of the present invention should not be construed
restrictively; advantages, features, and uses of the present
invention will become still more apparent from the following
description given with reference to the accompanying drawings.
Further, it should be understood that all appropriate modifications
made without departing from the gist of the present invention are
covered by the scope of the present invention. While various
embodiments of the present invention are described, it should be
understood that they have been presented by way of example only,
and not as a limitation. Thus, the breadth and scope of the present
invention should not be limited by any of the above-described
exemplary embodiments.
* * * * *